Hellish Devotion

What happens when a succubus, and the devil himself meet and fall in love? Even though it wasn't entended to happen that way?
When a simple deal with the devil became something more than just a deal. Lexi is faced with a decision 1. She can mate and help create a hybrid. Or 2. She can become human and have a normal life but will die 6 months later. The choice is her's and whatever choice she makes will change her life for good...
"Dear sweet girl you come to me and try to make a deal. Has anyone ever told you that's not smart?" Sighing she nodded. "I know there's a risk but I'm willing to take it." He spread a huge grin across his face. "Very well i will make this deal with you and give you power over yourself. I will also grant you your wish to be successful in life. But do know I will come to collect whenever I deem fit and you will have to make yet another choice, but you will not like either options." The girl agreed.